No power

[jaydavidson465]

My missus d40 is absolutely gutless. Like it has no boost. Idles fine, starts fine.
Replaced -
- suction control valve
- boost control valve solinoid
- vacuum hoses
Crimped off brake booster vacuum hose to rule that out.
Blocked off and unplugged the egr to rule that out.
Cleaned mass flow sensor.
Checked turbo impeller and is fine.
No codes on scan tool.
I’m stuck, any suggestions. Tia

 

[Chapster]

How gutless exactly? I presume it's not in limp mode or there would be codes.

Was it boosting fine and then fell off a cliff or a gradual decline?

Some other things worth checking:
- split charge air hose(s)
- split intercooler
- gummed up / grubby intercooler and/or inlet manifold

How many kms on the car? Does it have a catch can?

When you say you replaced the vac hoses, did that include the hard to reach one on the d/s near the vac pump? I know this can be overlooked because it's a PITA to get to.

I've also heard of the metal tubing on that side (which the vac hoses attach to) getting blocked and needing a clean out.

If you haven't already you could rule out both the above easily enough by testing the vacuum on the main hose from the vac pump to the BCS and see what you're getting.

Assuming good vacuum, how does it run if you bypass the BCS and connect the above line directly to the turbo actuator? I know you said you replaced the BCS but it's not guaranteed (if you bought from eBay) the "new" one will be working well. I know one I got was a dud out of the box.

I'm no expert but that's my 2 cents. There are others much wiser than me on here who could have some better suggestions.

 

[jaydavidson465]

How gutless exactly? I presume it's not in limp mode or there would be codes.

Was it boosting fine and then fell off a cliff or a gradual decline?

Some other things worth checking:
- split charge air hose(s)
- split intercooler
- gummed up / grubby intercooler and/or inlet manifold

How many kms on the car? Does it have a catch can?

When you say you replaced the vac hoses, did that include the hard to reach one on the d/s near the vac pump? I know this can be overlooked because it's a PITA to get to.

I've also heard of the metal tubing on that side (which the vac hoses attach to) getting blocked and needing a clean out.

If you haven't already you could rule out both the above easily enough by testing the vacuum on the main hose from the vac pump to the BCS and see what you're getting.

Assuming good vacuum, how does it run if you bypass the BCS and connect the above line directly to the turbo actuator? I know you said you replaced the BCS but it's not guaranteed (if you bought from eBay) the "new" one will be working well. I know one I got was a dud out of the box.

I'm no expert but that's my 2 cents. There are others much wiser than me on here who could have some better suggestions.

I did replace that hose right beside the vac pump, also I did bypass the solenoid and put direct vacuum to the turbo, the actuator pulled all the way up and still no difference besides a squeal noise witch indicated to me there was a leak somewhere but I can’t find it, after looking with no success I drove it again, still no power and no squeal noise?

 

[Old.Tony]

Do you have any means of reading data from the ECU? I use a bluetooth ELM327 OBD2 adapter and an Android app called 'Torque'. If you can do this, monitor the boost pressure. It should sit somewhere below 10psi under very light driving, but on hard acceleration you should see it touching 20psi or slightly higher.

If you're not seeing that, connecting the actuator directly to vacuum might give you some results but the squeal concerns me. More often than not, the squeal will be from a boost leak, so look for oily emissions around the air path. It could also be coming from an exhaust leak - look for black sooty emissions particularly around the exhaust-turbo interface.